GEIFFITHS THE GEAMA GRASSES. 



409 



In southern Arizona there is a plant which has heretofore passed for B. bromoides, 

 so called. It is erect and has comparatively delicate stems and leaves. In southern 

 Texas, where the soil is more fertile, precipitation more abundant, and shade of shrub- 

 bery a more important factor, it has a lighter green color and the culms are more 

 inclined to become geniculate and often are decidedly so. In portions of the Mexican 

 highland, where I judge the conditions are similar to those of Texas, upon the ocean 

 slopes and apparently in portions of South and Central America the characteristics 

 of the Texas form are accentuated and the culms are decidedly geniculate and much 

 branched. In the West Indian islands the plant becomes still more modified into 

 an exceedingly variable form which is often depau- 

 perate, prostrate, or even slightly stoloniferous. In 

 the entire series I have as yet found no constant floral 

 distinctions except that the West Indian plants often 

 have greatly reduced spikes and prominently modi- 

 fied spikelets, which, however, always have typical 

 ones mixed with them. 



As stated above the Arizona-Texas plant has in 

 the past been referred to B. bromoides. It extends 

 in a typical form throughout the Mexican highland 

 at least as far as the Isthmus of Teh uan tepee. The 

 geniculate Mexican form received the specific name 

 filiformis from Fournier and the West Indian plant 

 was called Heterosteca juncifolia by Desvaux. For 

 the present it seems wise to recognize Desvaux's 

 species, although unfortunately his name can not be 

 used, and to include under that of Fournier the two 

 forms of the Mexican highland, one of which reaches 

 Arizona and is somewhat modified in Texas. Should 

 it appear wise in the future to separate these two 

 forms the erect one so typical of southern Arizona and 

 the highland of Mexico will have to receive a new 

 name. 



HERBARIUM SPECIMENS. 



West Indies: Wright 3S16, Cuba. Ricksecker 78, St. 

 Croix. Broadxvay, Tempe, St. George. Hart 559, 

 Gordon Town, Jamaica. Eggers 687, St. Thomas; 

 5650, Scarborough, Tabago Island. 



Fig. 57. — Bouteloua amerkana. a, 

 Spikelet; 6, c, lemma and palet of 

 first floret; d, rudiment; e, two 

 views of caryopsis. a, Scale 5; b-e, 

 scale 10. From Wright 3816. 



Panama: Hitchcock 8409. 

 ' There are two specimens, Elliot 138, Granada, and 

 Duss 3160, Guadaloupe, which appear a little different in habit. They are mainly 

 larger, ranker plants with even laxer spikes and with slightly shorter awns." 



29. Bouteloua repens (H. B. K.) Scribn. & Merr. 



Dinebra repens H. B. K. Nov. Gen. & Sp. 1 : 172. pi. 52. 1816. "Crescit ad littora 

 Oceani Pacifici prope Acapulco." My interpretation of this is based upon the figures 

 and descriptions. 



f Bouteloua bromoides Lag. Gen. & Sp. Nov. 5. 1816. Lagasca says the plant is 

 from Acapulco, which is the only reason for referring it to B. repens. He also says it 

 is an annual, but this would be an easy mistake to make. A later specimen from 



a Only the specimens in the National Herbarium are before me, as the last work on 

 this group is done; consequently, citation of specimens can not be as ample as it other- 

 wise might be. 



